summaryrefslogtreecommitdiffstats
path: root/drivers/misc/atmel-ssc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/misc/atmel-ssc.c')
-rw-r--r--drivers/misc/atmel-ssc.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/misc/atmel-ssc.c b/drivers/misc/atmel-ssc.c
new file mode 100644
index 0000000000..ee590c4a15
--- /dev/null
+++ b/drivers/misc/atmel-ssc.c
@@ -0,0 +1,281 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Atmel SSC driver
+ *
+ * Copyright (C) 2007 Atmel Corporation
+ */
+
+#include <linux/platform_device.h>
+#include <linux/list.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mutex.h>
+#include <linux/atmel-ssc.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <linux/of.h>
+
+#include "../../sound/soc/atmel/atmel_ssc_dai.h"
+
+/* Serialize access to ssc_list and user count */
+static DEFINE_MUTEX(user_lock);
+static LIST_HEAD(ssc_list);
+
+struct ssc_device *ssc_request(unsigned int ssc_num)
+{
+ int ssc_valid = 0;
+ struct ssc_device *ssc;
+
+ mutex_lock(&user_lock);
+ list_for_each_entry(ssc, &ssc_list, list) {
+ if (ssc->pdev->dev.of_node) {
+ if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc")
+ == ssc_num) {
+ ssc->pdev->id = ssc_num;
+ ssc_valid = 1;
+ break;
+ }
+ } else if (ssc->pdev->id == ssc_num) {
+ ssc_valid = 1;
+ break;
+ }
+ }
+
+ if (!ssc_valid) {
+ mutex_unlock(&user_lock);
+ pr_err("ssc: ssc%d platform device is missing\n", ssc_num);
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (ssc->user) {
+ mutex_unlock(&user_lock);
+ dev_dbg(&ssc->pdev->dev, "module busy\n");
+ return ERR_PTR(-EBUSY);
+ }
+ ssc->user++;
+ mutex_unlock(&user_lock);
+
+ clk_prepare(ssc->clk);
+
+ return ssc;
+}
+EXPORT_SYMBOL(ssc_request);
+
+void ssc_free(struct ssc_device *ssc)
+{
+ bool disable_clk = true;
+
+ mutex_lock(&user_lock);
+ if (ssc->user)
+ ssc->user--;
+ else {
+ disable_clk = false;
+ dev_dbg(&ssc->pdev->dev, "device already free\n");
+ }
+ mutex_unlock(&user_lock);
+
+ if (disable_clk)
+ clk_unprepare(ssc->clk);
+}
+EXPORT_SYMBOL(ssc_free);
+
+static struct atmel_ssc_platform_data at91rm9200_config = {
+ .use_dma = 0,
+ .has_fslen_ext = 0,
+};
+
+static struct atmel_ssc_platform_data at91sam9rl_config = {
+ .use_dma = 0,
+ .has_fslen_ext = 1,
+};
+
+static struct atmel_ssc_platform_data at91sam9g45_config = {
+ .use_dma = 1,
+ .has_fslen_ext = 1,
+};
+
+static const struct platform_device_id atmel_ssc_devtypes[] = {
+ {
+ .name = "at91rm9200_ssc",
+ .driver_data = (unsigned long) &at91rm9200_config,
+ }, {
+ .name = "at91sam9rl_ssc",
+ .driver_data = (unsigned long) &at91sam9rl_config,
+ }, {
+ .name = "at91sam9g45_ssc",
+ .driver_data = (unsigned long) &at91sam9g45_config,
+ }, {
+ /* sentinel */
+ }
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id atmel_ssc_dt_ids[] = {
+ {
+ .compatible = "atmel,at91rm9200-ssc",
+ .data = &at91rm9200_config,
+ }, {
+ .compatible = "atmel,at91sam9rl-ssc",
+ .data = &at91sam9rl_config,
+ }, {
+ .compatible = "atmel,at91sam9g45-ssc",
+ .data = &at91sam9g45_config,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids);
+#endif
+
+static inline const struct atmel_ssc_platform_data *
+ atmel_ssc_get_driver_data(struct platform_device *pdev)
+{
+ if (pdev->dev.of_node) {
+ const struct of_device_id *match;
+ match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node);
+ if (match == NULL)
+ return NULL;
+ return match->data;
+ }
+
+ return (struct atmel_ssc_platform_data *)
+ platform_get_device_id(pdev)->driver_data;
+}
+
+#ifdef CONFIG_SND_ATMEL_SOC_SSC
+static int ssc_sound_dai_probe(struct ssc_device *ssc)
+{
+ struct device_node *np = ssc->pdev->dev.of_node;
+ int ret;
+ int id;
+
+ ssc->sound_dai = false;
+
+ if (!of_property_read_bool(np, "#sound-dai-cells"))
+ return 0;
+
+ id = of_alias_get_id(np, "ssc");
+ if (id < 0)
+ return id;
+
+ ret = atmel_ssc_set_audio(id);
+ ssc->sound_dai = !ret;
+
+ return ret;
+}
+
+static void ssc_sound_dai_remove(struct ssc_device *ssc)
+{
+ if (!ssc->sound_dai)
+ return;
+
+ atmel_ssc_put_audio(of_alias_get_id(ssc->pdev->dev.of_node, "ssc"));
+}
+#else
+static inline int ssc_sound_dai_probe(struct ssc_device *ssc)
+{
+ if (of_property_read_bool(ssc->pdev->dev.of_node, "#sound-dai-cells"))
+ return -ENOTSUPP;
+
+ return 0;
+}
+
+static inline void ssc_sound_dai_remove(struct ssc_device *ssc)
+{
+}
+#endif
+
+static int ssc_probe(struct platform_device *pdev)
+{
+ struct resource *regs;
+ struct ssc_device *ssc;
+ const struct atmel_ssc_platform_data *plat_dat;
+
+ ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL);
+ if (!ssc) {
+ dev_dbg(&pdev->dev, "out of memory\n");
+ return -ENOMEM;
+ }
+
+ ssc->pdev = pdev;
+
+ plat_dat = atmel_ssc_get_driver_data(pdev);
+ if (!plat_dat)
+ return -ENODEV;
+ ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;
+
+ if (pdev->dev.of_node) {
+ struct device_node *np = pdev->dev.of_node;
+ ssc->clk_from_rk_pin =
+ of_property_read_bool(np, "atmel,clk-from-rk-pin");
+ }
+
+ ssc->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &regs);
+ if (IS_ERR(ssc->regs))
+ return PTR_ERR(ssc->regs);
+
+ ssc->phybase = regs->start;
+
+ ssc->clk = devm_clk_get(&pdev->dev, "pclk");
+ if (IS_ERR(ssc->clk)) {
+ dev_dbg(&pdev->dev, "no pclk clock defined\n");
+ return -ENXIO;
+ }
+
+ /* disable all interrupts */
+ clk_prepare_enable(ssc->clk);
+ ssc_writel(ssc->regs, IDR, -1);
+ ssc_readl(ssc->regs, SR);
+ clk_disable_unprepare(ssc->clk);
+
+ ssc->irq = platform_get_irq(pdev, 0);
+ if (ssc->irq < 0) {
+ dev_dbg(&pdev->dev, "could not get irq\n");
+ return ssc->irq;
+ }
+
+ mutex_lock(&user_lock);
+ list_add_tail(&ssc->list, &ssc_list);
+ mutex_unlock(&user_lock);
+
+ platform_set_drvdata(pdev, ssc);
+
+ dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",
+ ssc->regs, ssc->irq);
+
+ if (ssc_sound_dai_probe(ssc))
+ dev_err(&pdev->dev, "failed to auto-setup ssc for audio\n");
+
+ return 0;
+}
+
+static int ssc_remove(struct platform_device *pdev)
+{
+ struct ssc_device *ssc = platform_get_drvdata(pdev);
+
+ ssc_sound_dai_remove(ssc);
+
+ mutex_lock(&user_lock);
+ list_del(&ssc->list);
+ mutex_unlock(&user_lock);
+
+ return 0;
+}
+
+static struct platform_driver ssc_driver = {
+ .driver = {
+ .name = "ssc",
+ .of_match_table = of_match_ptr(atmel_ssc_dt_ids),
+ },
+ .id_table = atmel_ssc_devtypes,
+ .probe = ssc_probe,
+ .remove = ssc_remove,
+};
+module_platform_driver(ssc_driver);
+
+MODULE_AUTHOR("Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>");
+MODULE_DESCRIPTION("SSC driver for Atmel AT91");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ssc");